NES 2.0 Mapper 382

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NES 2.0 Mapper 382 denotes the 830928C circuit board, used on a 512 KiB 5-in-1 and a 1 MiB 9-in-1 multicart containing the BNROM game Journey to the West and Capcom/Konami UNROM games.

The written address sets the mode and outer bank number, the data latch the inner bank number. The data latch is subject to bus conflicts, making it difficult to write a desired inner bank value as long as the outer bank is not locked.

Outer Bank register ($8000-$FFFF, write)

Mask: $8000

A~FEDC BA98 7654 3210
  1... .... ..LM UPPP
              || |+++- PRG A19..A17 (outer 128 KiB PRG-ROM bank)
              || +---- 0: UNROM mode
              ||       1: BNROM mode
              |+------ 0: Vertical mirroring
              |        1: Horizontal mirroring
              +------- 1: Lock outer bank
Power-on value: $00

Inner Bank register ($8000-$FFFF, write)

Mask: $8000

D~7654 3210 (bus conflicts)
  .... .ABB
        |++- In BNROM mode: PRG A16..A15 (inner 32 KiB PRG-ROM bank)
        +++- In UNROM mode: PRG A16..A14 (inner 16 KiB PRG-ROM bank
                                          at CPU $8000-$BFFF)